The CRW1 Index: Identification of Eyes with Previous Myopic Laser Vision Correction Using Only a Swept-Source OCT Biometer

PURPOSE: To develop and test a novel index (Cooke−Riaz−Wendelstein [CRW1]) that uses swept-source optical coherence tomography (SS-OCT) biometry measurements (IOLMaster700, Zeiss Meditec), including total keratometry, to alert clinicians that previous myopic laser vision correction (M-LVC) was present in a measured eye. DESIGN: Retrospective, multicenter, comparative diagnostic analysis. METHODS: The study took place at 6 centers in the United States and Austria. Anonymized SS-OCT biometry datasets acquired between 2018 and 2020 and containing 49,199 eyes were analyzed. The LVC status, as identified by the biometrist, was used to segregate eyes into LVC and non-LVC eyes. Data were split into training (10,780 eyes) and validation (38,419 eyes) sets. Subset analysis was performed for CRW1 Index accuracy compared to posterior/anterior corneal curvature ratio (Rpost/Rant), topography with corneal analysis software (Atlas 9000 with Pathfinder II, Zeiss Meditec), tomography (Pentacam, Oculus), dual Scheimpflug−Placido system (Galilei G6, Ziemer), and a cloud-based platform for cataract surgery planning (Veracity, Zeiss Meditec). A positive predictive value (PPV) of ≥90% was targeted for the CRW1 index. True positives, true negatives, sensitivity, and specificity were recorded. RESULTS: The CRW1 Index compared favorably against Rpost/Rant showing a higher PPV (93% vs 65%), with fewer false-positive results (29 vs 180). CRW1 performed similarly to topography software and better than the corneal imaging devices. The CRW1 cutoff value can be adjusted to increase sensitivity (CRW1-IS) to detect additional M-LVC eyes. CONCLUSIONS: The CRW1 and CRW1-IS indices offer surgeons and researchers a readily accessible method to use only SS-OCT biometry measurements to detect eyes with a high probability of previous M-LVC.

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Work Title The CRW1 Index: Identification of Eyes with Previous Myopic Laser Vision Correction Using Only a Swept-Source OCT Biometer
Open Access
  1. David L. Cooke
  2. Kamran M. Riaz
  3. David A. Murphy
  4. Oliver Findl
  5. Achim Langenbucher
  6. David Gu
  7. Surendra Basti
  8. Nathan Cannon
  9. Seth M. Pantanelli
  10. Matthias Bolz
  11. Jascha Wendelstein
  1. Myopic laser vision correction (M-LVC)
  2. Keratometry
  3. Total keratometry
  4. Swept-source ocular coherence tomography (SS-OCT) biometry
License CC BY-NC-ND 4.0 (Attribution-NonCommercial-NoDerivatives)
Work Type Article
  1. American Journal of Ophthalmology
Publication Date November 10, 2022
Publisher Identifier (DOI)
Deposited February 28, 2023




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Work History

Version 1

  • Created
  • Added PrePrint_File_-_Manuscript_and_Tables.docx
  • Added Creator David L. Cooke
  • Added Creator Kamran M. Riaz
  • Added Creator David A. Murphy
  • Added Creator Oliver Findl
  • Added Creator Achim Langenbucher
  • Added Creator David Gu
  • Added Creator Surendra Basti
  • Added Creator Nathan Cannon
  • Added Creator Seth M. Pantanelli
  • Added Creator Matthias Bolz
  • Added Creator Jascha Wendelstein
  • Published
  • Updated Keyword, Publication Date Show Changes
    • Myopic laser vision correction (M-LVC), Keratometry, Total keratometry, Swept-source ocular coherence tomography (SS-OCT) biometry
    Publication Date
    • 2023-03-01
    • 2022-11-10
  • Updated